Your systems and peripherals are constantly at risk of sustaining electrical damage, whether the culprit is improper site wiring, fluctuations in a system's electrical supply, overtaxed circuits, or lightning strikes. These precautionary measures will help you prevent the destructive consequences of electrical mishaps.
This article is also available as a PDF download.
PCs, servers, switches, routers, broadband modems, KVM switches, and other computer equipment are all subject to electrical damage. From improper site wiring to lightning strikes, a wide variety of electrical issues threaten systems and peripherals constantly. Review these 10 items to ensure that you've taken necessary precautions to help protect against data loss and equipment damage.
#1: Verify electricity levels
Most computer equipment is designed to use 120 volts of AC power supplied at 60 Hertz. Electrical current provided by a local utility or throughout a site or facility can vary from that standard, however, sometimes significantly.
When deploying new systems, and as facilities are expanded and adjoining sites grow, be sure the local power grid continues providing proper electrical baselines. Both sags and surges adversely affect PC and server electrical components and can lead to subsequent failures and data loss.
Use a multimeter to reveal the voltage an AC power outlet provides to systems and equipment (Figure A). If baselines vary by two percent or less, invest in electrical conditioning equipment, such as an uninterruptible power supply (UPS). If baselines vary by three percent or more, contact the local utility, a licensed electrical contractor, or facilities management to explore and correct the errors.
|A multimeter reveals a UPS power outlet provides 121.5 volts of AC electricity.|
#2: Confirm that supply circuits are grounded properly
Surge protectors and UPS devices can't properly safeguard the sensitive hardware they're designed to protect if the electrical outlets they're plugged into aren't properly grounded. Ground wiring is responsible for diverting most power surges. When ground wiring is compromised, surges don't have an effective suppression path. Expensive servers, PCs, and network equipment can subsequently suffer significant damage.
Information technology professionals typically aren't responsible for a facility's wiring quality, but as they're responsible for maintaining the computer systems and networks powered by the facility's electrical supply, IT pros have an interest in ensuring electrical outlets and power supplies are properly grounded.
Many UPS and surge protector models will light a warning lamp if the outlet into which they're plugged isn't properly grounded. Most do-it-yourself and hardware stores also sell inexpensive circuit testers (Figure B) that are simply plugged into outlets to confirm that circuits are grounded properly.
|A simple circuit tester can quickly confirm that power outlets are grounded properly.|
Whenever deploying new equipment, be sure to first test the circuit. When using surge protectors or UPS devices that feature improper-grounding alarms, also verify that the alarm light isn't lit.
#3: Don't overload circuits
Remember the Christmas Story scene in which Ralphie's dad blows a fuse connecting too many electrical plugs into a single outlet? In the popular holiday movie, a string of decorative lights is to blame, but too many desktop computers, servers, and network devices connected to a single circuit can easily overpower the electrical supply. Notice I didn't say too many desktop computers, servers, and network devices connected to a single outlet.
Splitting outlets (using power strips, surge protectors, and UPS devices), of course, does nothing but multiply the power demands placed upon the circuit to which those outlets are connected. Placing excessive demands upon a circuit can result in intermittent power failures, wide variations in available electricity, and even fire hazards as overworked circuits exceed safe operating ranges.
As CPU speeds and capacities and video card capabilities, among other elements, have increased, server and PC power requirements have grown as well. Carefully research your server room or office's power requirements to make sure the site's electricity requirements are sufficient.
Several resources are available for helping estimate appropriate power levels. Check out these sources for more information:
- Calculating Total Power Requirements for Data Centers (APC White Paper)
- Powering the Data Center Efficiently (Hewlett-Packard White Paper)
- System Power and Cooling Requirements (Sun Microsystems Book Chapter)
#4: Use a UPS/surge protector
Avoid deploying unprotected power strips, which do nothing to protect connected equipment from sags, surges, and lightning strikes. Deploy surge protectors and UPS devices instead.
Connect all sensitive electronic equipment to UPS or surge protection devices. Remember that a laser printer's fusers generate strong bursts of electrical consumption that can damage UPS units.
Mobile systems pose a particular challenge. Ensure that all traveling employees carry and use effective surge protectors when traveling with laptops.
#5: Properly calculate UPS/surge protector capacity
Just as electrical circuits can easily be overwhelmed, so too can a UPS device's power capacity be exceeded. Carefully calculate the power demands for the systems attached to a UPS device to ensure that the UPS can power the connected equipment.
Most UPS manufacturers provide interactive calculators you can use to estimate the volts-amperes and watts required to power your systems. Use these links for more information:
- American Power Conversion Corp.'s product selection wizards
- Belkin product selection wizards
- Tripp Lite's product selectors
When selecting surge protectors, purchase models featuring a sufficient number of protected outlets. A five-outlet surge protector may cover five devices, but it does no good if additional unprotected outlets must be utilized for other systems or peripherals.
Also ensure the surge protector selected includes lightning protection. Without protection from common thunderstorms, a surge protector can prove useless in safeguarding sensitive computer equipment from electrical spikes, resulting in failed hardware and corrupt and lost data.
#6: Replace damaged or faulty UPS/surge protectors
When a surge protector or UPS sustains a significant electrical surge, such as occurs with a lightning strike, the device's internal electronics can fail. If warning lamps light, outlets stop operating, or batteries fail, replace the damaged component or the entire UPS or surge protection device. You should do this even if the unit's telecommunications protective mechanism is the only component that fails.
Although it's tempting to continue using a UPS with only a single dead outlet or port, the fact the device sustained an electrical charge sufficient to damage components indicates that other damage may have occurred. Such damage could prevent the UPS or surge protector from properly protecting connected equipment, thus necessitating the device's replacement.
#7: Protect telecommunications links
Always make sure that servers, PCs, and network equipment receive protection from electrical spikes that can travel telecommunications links. Lightning strikes frequently discharge via cable modem, DSL, and telephone lines. The discharge isn't pretty, as everything from network interface cards to motherboards can be destroyed.
When purchasing UPS and surge protection devices, look for models that protect connected equipment from lightning strikes entering the network via data lines. Then, when deploying the UPS or surge protector, be sure to connect the data line to the protective device's input. Connect a corresponding RJ-11 or RJ-45 cable to the device's protected output to guard against lightning damage on your network.
#8: Test power supplies
Delicate electronic components within a computer, such as hard disk motors, memory, video cards, and motherboards, are sensitive to even minor fluctuations in a system's electrical supply. Even if circuits have been tested, proper grounding has been verified, and UPS or surge protectors are in place, a system's wayward power supply can inflict electrical damage on a PC or server.
Power supplies are a frequent cause of system reboots and failures. I've seen a power supply (on a system attached only to a power strip) continually reboot a machine while in the process of overheating. Thick, acrid white smoke poured from the malfunctioning power supply while the system kept repeating vain attempts to restart.
Whenever you encounter unexplained or intermittent reboots and other flaky behavior, check the power supply's electrical output to ensure it's working properly. Use either a multimeter, set to read the proper voltages, or a tool specifically designed to test a power supply's output (Figure C).
|Devices such as this Vastech ATX 2.0 Power Supply Tester make testing power supplies easy.|
Malfunctioning power supplies should be replaced immediately to protect a system's components from electrical damage and potential fire hazards. If a power supply has been distributing excessive electrical power to a system, it's not a bad idea to test the motherboard, CPU, memory, and other components using a POST card to make sure that no additional repairs are required.
#9: Maintain proper operating temperatures
Temperature is a well-known and well-documented enemy of network switches, firewalls, PCs, servers, and other equipment. High temperatures can adversely affect power supplies, potentially causing damage to a system's internal components. High temperatures can also prevent a UPS device's internal electronics from working properly, thereby leaving connected systems and equipment at risk.
Protect against electrical damage resulting from overheating by ensuring that systems receive proper cooling. Keep all vents and fan outlets free of debris, boxes, files, folders, and other furniture. When performing routine system maintenance, verify that PC and server exhaust fans are working properly and are unobstructed.
I've encountered situations in which a PC's exhaust fans were blocked by documentation placed inside the system (to prevent the discs and license numbers from becoming separated from the unit or being lost). A good idea in theory, but the resultant ventilation loss prompted the hard disk to fail as a result of its baking in the heat generated by its own electrical activity.
Take steps to ensure that UPS devices also receive ample room to breathe. Don't stack boxes, retired PCs, or other equipment alongside UPSes, either in server rooms or in cubicles.
Electricity use consistently generates heat, and that heat must be dissipated properly or damage and potential data loss will result. It sounds simple, but take a quick walk through any office environment and you'll almost always find at least one UPS buried by boxes, files, or other office material.
#10: Maintain proper insurance
You can take numerous steps to prevent electrical damage to computers, servers, and other computing equipment, but sometimes your best efforts simply aren't sufficient. I've seen clients lose motherboards, NICs, hard disks, and more due to lightning strikes. Some of the damaged equipment was even connected to UPS and surge protectors.
Despite precautions, equipment can still end up being lost to electrical damage resulting from surges, lightning, and other disturbances. Business owners, even those with small operations, should make sure that insurance policies include riders or passages expressly covering computers and associated equipment. IT professionals employed by larger organizations should also work with their CTOs to properly maintain documentation required by the corporation's insurers.
Review your organization's property and casualty insurance